Biorecognition elements antibodies

This biosensor consists of two surface-tethered components. The biorecognition element can be an antibody (Section 19-5), DNA, RNA, or carbohydrate with specific affinity for analyte. A structural analog of the analyte is bound to a flexible arm adjacent to the recognition element. In the absence of analyte, the tethered analog binds to the recognition element. 

Pohanka, M. (2009) MonodonaJ and polyclonaJ antibodies production-preparation of potent biorecognition element. Journal of Applied Biomedicine, 7 (3), 115-121. 

In the sandwich assay format, two biorecognition elements directed to either the same epitope present multiple times on the analyte surface or the different epitopes on the target analyte are utilized. For immunoassays, this format is useful for large analytes with multiple antigenic sites. Here, one antibody is immobilized onto a porous membrane and serves as the capture antibody, while the other is conjugated to a detectable species. The response is directly proportional to the concentration of analyte in the sample. A band consisting of a secondary antibody may also be present to serve as a control that the assay components worked and the assay was run correctly. This assay format is depicted in Fig. 4. 

Direct detection of antibody against insulin in patient sera using an SPR sensor Biacore 2000 is presented in [50]. Purified human insulin was used as a biorecognition element and immobilized on the sensor surface via amine coupling chemistry. Test sera samples were pretreated to remove insulin and filtered before SPR measurements. Insulin antibodies were detected in eight selected patient sera samples and fell in the range 2.91-16.3 xgmL ... 

Choice of biorecognition element. What biorecognition element will be used Is it tailored for the application The use of materials (e.g., antibodies) produced for other assay formats often results in poor-quality sensors, as the properties of the antibody may not be customized for the format chosen. 

Molecular recognition is central to biosensor technology. Receptors, enzymes, antibodies, aptamers, molecular beacons, and nucleic acids are mainly used as molecular recognition elements in biosensor development (Chambers etal., 2008). Since 1990, nucleic acids, especially deoxyribonucleic acid (DNA) have been used as biorecognition elements in biosensor technology. These biosensors are named as DNA-based biosensors. 

Traditionally, antibodies have been the main biorecognition elements used. Antibodies have been applied in various biosensor platforms including electrochemical, fluores-cent, o and colorimetric assays. Antibodies provide varying stringency of interactions depending on whether they are monoclonal or polyclonal. Monoclonal antibodies... 

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